The invention relates to optical fiber connectors. More particularly the present invention relates to a multiple component optical fiber connector which reduces assembly errors and defects.
Optical fiber connectors are extremely important to make critical mechanical connections between the free ends of optical fibers. It is important that the connectors securely retain the connection between the two pieces of optical fiber. A variety of connectors have been developed to provide such connection. For example, U.S. Pat. No. 5,073,044 to Egner et al., issued Dec. 17, 1991, assigned to the Assignee of the present invention, shows an optical fiber connector having a right angle strain relief.
The general design of the Egner device is representative of optical fiber connectors. Such a connector includes a tubular body including a ferrule, a coupling nut, biasing means and a retaining ring. The coupling nut and biasing means are axially arranged on the tubular body and retained in position by the retaining ring. The biasing means acts against the coupling nut to provide a secure engagement with the other coupling component with which it is connected.
Typically, the retaining ring used with this type of connector is a C-ring having an open gap along one side for radial attachment to the tubular body. The C-ring is mated with an annular groove formed on an outside surface of the body. U.S. Pat. No. 5,121,455 to Palecek, issued Jun. 9, 1992, is an example of a C-ring used to retain a coupling nut and spring on the body of an optical fiber connector.
It would be desirable to provide an optical fiber connector which could be assembled using automated procedures. The C-ring retaining ring due to its radial assembly is not conducive to reliable automated assembly. However, the C-ring retaining ring, or other manual attachment procedures may be a necessary fallback assembly technique in the event of downtime of an automated assembly machine. It is important to provide the ability to use both manual and automated assembly techniques in order to maintain the required level of production output for the optical connectors.
A problem which may occur during the assembly of an optical fiber connector is that the biasing means or spring may become trapped or lodged between the coupling nut and the elongated body. The connector is assembled by axially aligning and telescopically stacking the coiled spring and coupling nut on the elongated body. This problem may occur in connectors which use an elongated body having an annular groove for accepting C-rings. During the assembly process, the spring is positioned on the elongated body and the coupling nut is positioned over the spring and the elongated body. As the spring is compressed along the elongated body by the downward movement of the coupling nut, the spring may shift with a trailing end coil of the spring shifting into the annular groove in the elongated body. Continued downward movement of the coupling nut may wedge or trap the trailing end coil in the groove resulting in a defectively assembled connector.